Process and machine for opening bivalves



March 15, 1966 LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet l I--'W- 24 i U I /22 i i l i;23 23 i i I 46 Fl G I INVENTORS James M. Lupeyre& Robert F. Couret ATTORNEYS March 15, 1966 LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 2 INVENTORS Fl G 2 James M. Lopeyrea Robert F. Couret MMMWRW AM ATTORNEYS March 15, 1966 J. M. LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 4 mr l INVENTORS James M.Lc|peyre 8 F l G 5 Robert F. Couret ATTORNEYS March 15, 1966 J. M. LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet INVENTORS James M. Lopeyrea Robert E Couret W MW March 15, 1966 LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 6 FIG.9.

INVENTORS James M. Lopeyre 8\ Robert F. Courei MM 53 1M ATTORNEYS March 15, 1966 J. M. LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 7 tg ml 8 o o a 0 9 o o 8 0 o 0 0 o o o g; o o co 0 0| 0 00 o 0 3 0 0 N 0 o I w o O 'J 0 o o I IO 0 o L m m o G O o (D o 0 g h o I m o O O I F o o I m 0 I w o o o L Z P on (I o m o o O: cs I o 0 O 9 ml I 1 o o i o o {8 0 Q 0 o o l 0 LL.

a) O 2 LL w w o o m a) 0 o 8 o m 8 (h m 0 O \4 a, 0 o I 0 O 0 o c0 0 g o o L o o o 0 r0 0 m Q O O o a o 0 o o o o 0 /INVENTORS m U James M. Lupeyrefi Robert F. Couret MMMMM g ATTORNEYS March 15, 1966 P Y E ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 8 domes M.Lc|peyre 8 Robert F. Couret' Ib-JLWMM gm ATTORNEYS March 15, 1966 J LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 9 FIG James MlLclpeyre 8:

Robert F. Couret mmmm g M ATTORNEYS March 15, 1966 J. M. LAPEYRE ETAL 3,239,377

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 10 a E WW MP0 W 00 N w Mil m. 0E fl u Ill/IA 1 M@ MR 0 5 nu NMNW J. M. LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES 14 Sheets-Sheet 11 INVENTORS James M. Lapeyre Robert F. Couret mfimx mwm mam I ATTORNEYS March 15, 1966 Filed Feb. 16, 1965 March 15, 1966 J. M. LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES 14 Sheets-Sheet 12 Filed Feb. 16, 1965 INVENTORS James M. Lapeyre& Robert E Couret BY I n7 AM g ATTORNEYS March 15, 1966 LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES Filed Feb. 16, 1965 14 Sheets-Sheet 13 HIGH PRESSURE FLUID SUPPLY 04b PIPE I040 Ill V r r i r A V I I V A A amunlla annular/111111 INVENTORS 9 James M. Lupeyre a 280 Robert E Couret FIG.I6. MW C Q ATTORNEYS March 15, 1966 J. M. LAPEYRE ETAL 3,239,877

PROCESS AND MACHINE FOR OPENING BIVALVES l4 Sheets-Sheet 14 Filed Feb. 16, 1965 I04b HIGH PRESSURE FLUID SUPPLY PIPE I040 2 INVENTOR5 James M. Lopeyrea Robert F. Couret MWJW M FIG.I7.

ATTORNEYS United States Patent 3,239,877 PROCESS AND MACHINE FOR OPENING BIVALVES James M. Lapeyre and Robert F. Couret, New Orleans,

La., assignors to The Laitram Corporation, New 0rleans, La., a corporation of Louisiana Filed Feb. 16, 1965, Ser. No. 436,417 39 Claims. (Cl. 179) The present invention relates to Process and Machine for Opening Bivalves and is a continuation-in-part of our similarly-entitled application, Serial No. 274,124, fi-led April 19, 1963, and has for .an object to provide a process and machine for shucking oysters and the like to recover the edible meat from either live fresh oysters or from oysters previously frozen, as for instance such frozen oysters as are treated in prior United States Patent 3,007,801, granted November 7, 1961, entitled Process for the Recovery of Oyster Meats, and United States Patent 3,037,237, granted June 5, 1962, entitled Machine for Shucking Oysters.

According to those prior patents it was desirable to partially thaw the frozen oysters incident to the shucking operation, which partial thawing may be eliminated as a necessity pursuant to the present invention so far as the same relates to its treatment of frozen oysters.

The edible meat of oysters is enclosed in a shell composed of two valves, a deep valve and a shallow valve, hinged together at the narrow end of the shell and having an adductor muscle associated with the meat attached to both valves near the center of the large round portion of the shell. The adductor muscle functions to open and close the valves to permit drawing into the shell of food and sea water.

Incident to the recovery of oyster meats it is highly desirable to recover also the juices and liquors which are highly regarded and which are substantially wholly recoverable in frozen oysters. However, in the case of unfrozen oysters such juices and liquors are largely lost in hand shucking and in opening oysters with the edge wise dimension of the oyster in a vertical or upright plane.

It is accordingly another object of the invention to so orient and retain throughout the shucking operation the oyster so that its plane of cleavage between the thin meeting free edges of the valves shall be disposed in a substantially horizontal plane, preferably with the deep valve below which retains the juices and liquors when the top shallow valve is shifted edgewise to expose the meat.

It is a further object of the invention to so conduct the process and machine as to shear the adductor muscle of frozen oysters from at least one of the valves, usually the shallow valve, and to break the attachment of the hinge so that the oyster meat to and including the liquor and juices are exposed for decanting of the juices and liquors and removal of the oyster meat for easy access to sever the adductor muscle from the bottom deep valve.

The invention has for its further purpose to recover oyster meats in a manner to preserve the integrity of such meats as no entry is made into the shell, unlike the action of the shucking knife.

In the case of frozen oysters it is an object of the invention to operate upon the shell and the valves thereof which results in recovery of the oyster meats to and including the juices and liquors all in a frozen state so that no loss of meat or liquors in entailed.

It is a still further object of the invention to provide a process and machine for quantity production whereby, in an automatic manner, large quantities of bivalves may be opened in a minimum of time to the end of substantially lowering market prices.

3,239,877 Patented Mar. 15, 1966 With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more. particularly pointed out in the claims appended hereto.

In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views:

FIG. 1 is a front elevational view of one form of machine for carrying out the process of opening oysters or other bivalves in accordance with the present invention.

FIGURE 2 is a side elevational view of the same.

FIGURE 3 is a fragmentary vertical sectional view taken on a much magnified scale showing a form of clamp members in position in clamping engagement with an oyster.

FIGURE 4 is a similar view showing the upper clamp member in substantially the same position with the lower clamp member having been shifted angularly with corresponding movement of the lower deep valve with which it has been entrained.

FIGURE 5 is a view similar to FIGURE 3 with the upper clamp shown in full lines in raised position and in dotted lines in a partially lowered position and with the oyster resting in an initial position upon the yieldable upwardly projected pins forming the shell-grasping unit of the lower clam-p member.

FIG. 6 is a horizontal sectional view taken through the upper clamp member at pin line showing a form of pin locking device.

FIGURE 7 is a horizontal sectional view through a portion of the machine at pin level of the lower clamp member illustrating in full and dotted lines a form of motor and connection for twisting or rotating the lower clamp member.

FIG. 8 is a view similar to FIGRE 7 showing the rocked or rotated position of the lower clamp member.

FIGURE 9 is a fragmentary perspective view of an automatic machine for accomplishing the opening of the bivalves with parts broken away and parts shown in sectron.

FIGURE 10 is a longitudinal vertical sectional view taken through the forward portion of the machine illustrating the conveyor and its mounting.

FIGURE 11 is a top plan view of the complete machine with the top cover removed and with parts shown in section.

FIGURE 12 is a vertical transverse sectional view taken through the machine showing parts in elevation and in section.

FIGURE 13 is a vertical sectional view taken on an enlarged scale through :a form of intermittent drive arrangement for the twist motion.

FIGURE 14 is a top plan View, taken on a reduced scale, of the drive device of FIGURE 13 illustrating also a form of return movement and a device for absorbing rotational impact incident to such return motion.

FIGURE 15 is a vertical longitudinal sectional view taken on the line 15-15 in FIGURE 11.

FIGURE 16 is a cross-sectional view taken on an enlarged scale through the upper clamping head, showing the preliminary action of a central pin.

FIGURE 17 is a similar view showing the position of the parts when the bivalve is tightly clamped in readiness for the twist or opening operation.

Referring more particularly to the drawings, 15 designates a suitable frame and 16 a standard rising therefrom, 17 a table and 18 a front control panel.

At a suitable point forwardly of the standard 16 and below the level of the table 17 is a lower clamp member designated generally at 19 which is supported for horizontal rotary or linear movement, shown as mounted for rotation in a rotary bearing support 20 in an orientation in which the lower clamp member 19 may rotate about a substantially vertical axis.

An upper complemental clamp member designated generally at 21 is aligned vertically above the lower clamp member 19. The upper clamp member is suitably supported for vertical up and down movement toward and from the complementary lower clamp member 19 by any suitable means, such for instance, as by a cross-head 22 appropriately fitted in guides 23 aflixed to the standard 16, such cross-head 22 being carried upon a plunger rod 24 of a fluid pressure motor 25 affixed to the upper portion of the standard 16.

Fluid connections 26 and 27 are indicated as connected to opposite ends of the motor 25 for driving the piston of the motor up or down by control means mounted upon the front control member 18 is hereinafter described.

Each of the clamp members 19, 21 is equipped with suitable shell-grasping means which in the single form of the invention illustrated are pluralities or gangs of rigid pins 28 and 29. The near free ends of these pins 28, 29 are adapted to close upon the oyster or other bivalve as indicated in FIGURE 3.

The pins 28 of the lower clamp member 19 are yieldably projected upwardly by any suitable means. Similarly, the pins 29 of the upper clamp member 21 are yieldably projected downwardly.

The means for so doing is preferably through the action of pneumatic or fluid pressure supplied from an appropriate source to fluid chests 30 and 31 (FIGURE carried by the respective clamp members 19 and 21. The inner ends of the pins 28 and 29 are spread or enlarged as indicated at 32 and 33 to provide stops for preventing the driving of the pins completely out of the chests 30 and 31.

The outer ends of the pins 28, 29 are preferably recessed as indicated at 34 in FIGURE 5 resulting in the formation of sharp circular rims 35 which engage the valves of the shell of the oyster.

Chest cover plates are indicated at 36 and 36, pin guide plates at 37 and 37 and intermediate locking plates at 38 and 38 All of these plates are perforated to slidably receive therethrough the pins 28 and 29.

The plates 36 and 37 are held immovably to the chest 30 as by bolts 53 or other appropriate fastenings. In like manner the chest cover plate 36 and the pin guide plate 37 are fixedly mounted to the upper fluid pressure chest 31 while the locking plates 38 and 38 float freely between the companion plates.

Any rotary or other pressure applied to the locking plates 38, 38 will tend to bind the pins 28, 29 against the walls of the perforations of the companion plates 36 and 37 and 36 and 37 This relative movement of the locking plates 38 and 38 may be accomplished in any suitable manner, one form of which is shown in the accompanying drawings in FIG- URES 6, 7 and 8 in the form of locking motors 39 and 39 preferably piston or reciprocating fluid pressure motors.

The motor 39 is pivoted at one end at 40 to a part of the lower clamp member 19 and rotates therewith as shown in FIGURES 7 and 8. The piston of the motor 39 is connected by a pivot 41 to an arm 42 of the locking plate 38.

In like manner the motor 39 as shown in FIGURE 6 its plunger end connected by pivot 41 to an arm 42 of the locking plate 38 It will be understood that very small linear movement of the piston or plunger rods of the motors 39, 39 will act to move the plates 38, 38 fractionally so that the walls of the perforations of all of the plates will be frictionally pressed against the sides of the pins 28, 29 to resist any sliding movement of the pins in an axial direction.

The lower clamp member 19 may be rotated under control in any appropriate manner as through an arm 43 aflixed to the lower clamp member 19 and connected 4 by a link 44 to the piston rod 45 of a fluid pressure motor 46 affixed to the frame as shown in FIGURE 2.

Referring more particularly to FIGURE 1, a clamp control valve is indicated at 47 having an operating handle 48 with cylinder connections as indicated to the opposite end fluid connections 26 and 27 of the elevating and lowering motor 25 for the upper clamp member 21.

This control valve 47 also has connections as marked to a source of fluid pressure and to an exhaust or return duct.

Also as shown in FIGURE 1, a lock control valve 49 is illustrated on the panel 18 under the control of an operating handle 50 and having similar connections as indicated to the locking motors 39 and 39.

Still referring to FIGURE 1, a twist control valve 51 under the control of an operating handle 52 is connected as indicated to a cylinder 46, these connections being also shown in FIGURE 2.

By swinging the operating handles 48, 50 and 52 into one or the other direction, fluid pressure may be admitted to opposite ends of the cylinders 25, 39, 39 and 46.

In operation, with the upper or overhead clamp member 21 in the raised position of FIGURES 1 and 2, an oyster or other bivalve is manually placed upon the lower clamp member 19 by resting the same upon the upper free ends of the pins 28 in the condition in which all pins are projected by the fluid pressure in the chest 30 to the uppermost extent of their projection in which the upper free ends 34 and 35 are substantially in horizontal alignment.

In the case of a raw, fresh oyster, it is greatly to be preferred that the deep valve A be placed lowermost and the shallow valve B upwardly so that the plane of cleavage C between the valves shall extend in a generally horizontal line.

Ordinarily, the free weight of the oyster will not be suflicient to depress any of the pins 28 and such pins constitute a deformable support for the oyster which is depressed down upon the pins when under the drive of the motor 25 the upper clamp member 21 descends forcibly upon the bivalve.

FIGURE 3 illustrates the clamped condition of the oyster between the two clamp members with the free ends of the pins 28 and 29 engaging opposite valves A and B. The downward effective pressure of the upper clamp member 21 acting through the pins 29 will cause both sets of pins 28 and 29 to be retracted in opposition to the fluid pressure in the chests in proportion to irregu larities encountered on the external surface configuration of the upper and lower valves A and E.

Central pins 28 and 29 will be retracted to the greatest linear extent owing to the greater vertical thickness of the oyster shell at the central portion.

The pin gangs will consequently deform to cavity patterns which agree with the external characteristics of the oyster shell. In the retracting movement of the pins, the same will be brought under greater pressure which will cause the outer ends of the pins to forcibly engage the shell. At this point the lever or handle 50 of the lock valve is thrown so as to actuate the two locking motors 39 and 39* causing the locking plates 38 and 38 to be shifted to lock the pins in the pattern indicated in FIGURE 3 which is the counterpart of the external configuration of the oyster.

After this locking operation has taken place, the handle 52 of the twist valve 51 is thrown so as to admit fluid under pressure to the far end of the cylinder 46 as seen in FIGURE 2 causing the motor to drive the piston rod 45 and link 44 in the manner indicated in dotted lines in FIGURE 7 to thereby rotate the lower clamp member 19 through a suitable angular distance which will eifect corresponding rotary movement in the lower valve A while the upper valve B is immobilized to the upper clamp member 21. The result is shown in FIGURE 4 in which the lower valve has been rotated through an appreciable angle relatively to the upper valve sufficient to break the hinge joint between the valves and also to twist and sever the adherence of the adductor muscle from one of the valves.

After this operation the pins are unlocked and the upper clamp member 21 raised so as to free the oyster from the clamping operation.

In FIGURE 1 the treated oyster which is opened is shown on the table 17 to the left of the clamp valve 47. The upper valve is then discarded and a knife may be used to sever the connection of the adductor muscle to the lower valve.

The process or method involves generally the steps of immobilizing both valves of an oyster. In the case of at least one valve this immobilizing step is brought about by relatively moving together the oyster in the shell and a deformable shell grasping means so that the grasping means will be deformed to alter its shape to the pattern of that part of that valve contacting the same for the purpose of immobilizing that valve to the grasping means and subsequently moving either valve relatively to the other in an edgewise movement substantially parallel to the line or plane of cleavage between the valves to open the bivalve.

A preferred process is to employ two such deformable grasping means as illustrated in FIGURE 3 and to utilize a clamping step which will insure that the pins or other grasping means will be variously retracted to cause the free ends thereof to very firmly engage the external surfaces of the two valves which surprisingly has the effect, in an oyster opening process, to in the first instance act to urge the two valves together to hold the same more firmly closed, but which step has, in an oyster opening process, the advantage of immobilizing both of the valves to their respective grasping means and immobilizing one of the valves absolutely so that when the companion valve is shifted, as a matter of entrainment to its grasping means, relatively to the absolutely immobilized valve, the bivalve will be opened and incident thereto the hinge between the valves will be broken and the attachment of the adductor muscle to at least one of the valves will be severed.

This relative movement between the valves may be carried out in a linear or rotary manner, the form of the invention illustrated in the drawings showing a rotary procedure in which the axis of rotation will be roughly vertical and roughly through the adductor muscle.

Referring more particularly to FIGURES 9 to 17, inclusive, and for the present to FIGURE 9, the lower clamp member is indicated at 19 from which the shellgrasping means or pins 28 project upwardly, which pins are normally in the upwardly projected position by reason of the body of fluid pressure beneath same.

This lower clamp member is carried by a slide or cross-head 60 vertically movable in a slide housing 61 carried fixedly by a bracket 62 or other structural member attached to the frame of the machine. The slide 60 and the clamp member 19 are moved up and down with a dwell period therebetween by a lower rocker arm 63, shown in FIGURE 12, as being rocked about the pivot 64 from a barrel cam 65.

The complementary upper clamp member 21 is disposed vertically above the lower clarnp member 19 and is provided with the retractile yieldably projected shell-grasping means or pins 29*. The upper head or clamp member 21 is also preferably movable up and down in a co-axial vertical line with the lower clamp member 19 and for this purpose the upper clamp member 21 is carried by a spline shaft 66 guided in bearings 67 and 68 and also rotatable in said bearings. The shaft 66 at its upper end portion has aflixed thereto a spherical bearing housing 69 engaged by the forward end of an upper rocker arm 70, shown more particularly in FIG- URE 12, as being pivoted intermediate its ends upon a 6 pivot 71 suitably mounted in the main frame of the machine which is indicated in this FIGURE 12 generally at 72. The inner or rear end of the upper rocker arm 70 carries a roller 73 which is a follower of the upper barrel cam 74.

As also shown in this FIGURE 12, rotary twist may be imparted to the spline shaft 66 through a sprocket 75 keyed to the spline shaft 66 and through which the spline shaft moves up and down vertically. The bearings 67 and 68 preserve the alignment of the sprocket 75 to a companion sprocket 76 driven periodically as later referred to. Transmission from sprocket 76 to 75 is through a chain 77.

Reverting to FIGURES 9 and 10, the clamp members 19 and 21 are located in an operating zone A through which moves the upper run of a conveyor in the direction shown by the arrow from a loading area B to a discharge or unload area C.

A form of conveyor comprises spaced-apart chains 78 and 79 to which are afiixed pallets 80 in any suitable manner. The chains run over pairs of sprockets 81, 82 affixed to a drive shaft 83 and other pairs of idler sprockets 84 on a shaft 86 and sprockets 87 on a shaft 88, and sprockets 89 on a shaft 90. These various shafts are mounted in bearings 91 and 92 (FIGURE 11) in a conveyor outer support plate 93 and the machine frame 72. The shaft 83 is driven step-wise or by intermittent motion with appropriate dwell periods from a motor as hereinafter described.

The shaft 88 for the sprockets 87 may be movably mounted in that its bearing 94 is carried by an arm 95 pivoted in the frame at 96 and connected to a turnbuckle or other adjusting device 97, 97*, as shown in FIGURES 9 and 10. By adjusting the device 97 the chain may be tightened or slackened. The conveyor chains may be equipped with suitable guides 98 to engage outside surfaces of the rails 98 (FIGURES 9 and 10) to cause the chain to properly track and preserve alignment. Horizontal stanchions 99 carried by the main frame may be used to support or assist in the support of the outer plate 93 in which the conveyor shaft bearings 91 are carried.

Each pallet 80 is provided with a group of holes 100 in number and position corresponding to the upstanding pins 28 to receive the pins 28 upwardly therethrough as hereinafter described. A group of supports or pegs 101 are mounted upon each pallet 80 in a grouping suitable to receive the lower valve of the oyster and to support the same in position where the lower valve will be exposed to the rising pins 28 of the lower clamp 19 as hereinafter described.

The upper clamp member 21 may or may not be provided with a stripping device which includes a sleeve 104 slidable up and down on member 21 and entrained to rotate with the member 21 by a pin 104 on member 21 occupying a vertical slot 104 in the sleeve. This sleeve 104 supports a stripping plate 103 provided with holes 102 in number and pattern corresponding to the number and pattern of the pins 29 of the upper clamp member so that the pins 29 will at all times occupy the holes 102. The sleeve 104 drops down by gravity until arrested by stop member 104 on sleeve encountering clamp member 21 Referring more particularly to FIGURES 12, 13 and 14, a form of device for communicating rotary motion to the upper clamp member 21 is shown. As shown in FIGURE 13, the sprocket 76 is mounted to a hub 105 rotatable on bearings 106 and 106 freely about the cam shaft section 107 When twist is required this hub 105 is rotated by the engagement against its anvil 108 by a projection 109 which extends downwardly from a yoke 110.

As shown more particularly in FIGURE .14, the yoke 110 has extension arms 111 and 112 pivoted at 113 to a hub plate 114 entrained to rotate by key 115 to the cam shaft section 107d. The yoke at the end opposite the pivot carries a roller 116 adapted to travel on a twist cam plate 117 held fixedly to the frame by a twist cam plate lock 118 (FIGURE 13). The plate 117 has mounted thereon an arcuate cam track or rail 119 in the path of the roller 116. The cam track 119 has end sections 119* and 119 which slope down to the elevation of the plate 117.

The yoke 110 rotates continuously and when its roller 116 is in the lower position traveling on the plate 117, the projection or dog 109 is in the path of and engages the anvil 108 thus imparting twist partial rotation to the sprocket 76 and its chain 77 and from the chain to sprocket 75 and the upper clamp head 21 However, when the roller rotates around to a position where it rides up the sloping surface 119* into the high cam rail 119, the projection 109 will be withdrawn upwardly from engagement with the anvil 108 thus releasing the twist mechanism to a device for restoring the same through counter rotation to an initial position. The arrangement will cause twist movements and consequent opening of the bivalve at prescribed intervals timed to the indexing movement of the conveyor so that the twisting operations occur during dwell periods of the conveyor when the bivalve is clamped between the upper and lower clamp members.

During the period that the roller 116 is riding on the high portion of the cam rail, the twist mechanism including the chain 77, sprockets 75 and 76 are released to the action of the return mechanism, a form of which is illustrated in FIGURE 14 and comprises a return coil spring 120 affixed at one end 121 to a part of the frame and its other end to a return chain 122 which is entrained about a return sprocket 123 affixed to the hub 105 and through the hub to the twist sprocket 76.

As seen in FIGURE 14 the other end of the return chain is connected to a plunger rod 124 of a dash pot cylinder or air-damped shock absorber 125 which is pivoted at 126 to a part of the machine frame. During the twist operation when the dog 109 is engaged and driving the anvil 108, the sprocket 123 will be rotated in a direction to expand the spring 120 and store potential energy therein. Upon release of the dog 109 from the anvil 108 the twist hub 105 will be released to the action of the extended spring 120 which through its return chain 122 will rotate the hub 105 and the two sprockets 76 and 123 in a counter rotation back to an origin point and the dash pot 125 will absorb the rotational impact against such reaction of the expansion spring 120.

Referring more particularly to FIGURE 15, and incidentally to FIGURE 11, power for the operation may be supplied by an electric or other motor 134 having a motor brake 135 and operating through a gear reducer 134 to drive a sprocket 134 engaged by a roller chain 128 which drives a sprocket 130 having a sprocket hub 130 This hub through a connection 130 drives a universal joint 130 a splined shaft 131 and a companion universal joint 129 for driving through flanged couplings 129, the input shaft of an indexing transmission 133 the output of which is to the conveyor drive shaft 83.

The sprocket 130 also drives a transmission input shaft 127 which rotates a bevel gear 127* and a follower bevel gear 127 on a transmission output shaft 107 upper section and 107 lower section. The upper shaft 107 is connected by a flexible coupling 136, 136 to the upper cam shaft section 107 The lower output transmission shaft 107 is connected through a flexible coupling 137, 137 to the lower cam shaft section 107 which is stepped in the lower bearing 138. The upper cam shaft section 107 has a bearing 139 also mounted in the frame.

The gears 127 and 127 are mounted in a gear casing 127.

The indexing transmission is a well-known form of drive, for instance, roller gear drive or Geneva mechanism (Ferguson drive). The purpose of such indexing transmission is for precision step-by-step movement of the conveyor so that at each stoppage the holes in the conveyor pallets 80 will register accurately with the pins 28 so as to permit movement of the pins upwardly through the pallets 80 to effect lifting of the bivalve off the plate and up into a clamping engagement with the upper pins 29 Referring more particularly to FIGURE 16, a central pin 29 is shown in addition to the pins 29*. This central pin 29 is also slidably mounted in the upper clamp head 21 and has a pointed or conical lower end adapted to engage the upper valve of the oyster is indicated. The upper end portion of the central pin 29 is exposed to air or other fluid pressure supplied to a head space in the lower end of the shaft 66 from a suitable source of supply, which supply is under relatively low pressure compared to the pressure in the chest 151 which is preferably hi h pressure oil under continuous pressure to which the upper ends of the pins 29 are subjected through restricted passages 152 in a partition 153.

The air pressure from the head space 150 preferably enters through an air-tight coupling 154 to the upper end of the central pin 29b which is slidable in a cylinder 155 in the upper clamping head. The pressure to the head 150 is supplied under controlled valve or other arrangement.

In operation of that form of the invention shown in FIGURES 9 to 17 inclusive, fresh oysters or other bivalves in the shell are placed by hand or otherwise on the pegs 101 at the loading station B. The deep shell will preferably be placed lowermost.

In this position the bivalves will be carried from the loading station B to the operation station A where each pallet 80 is in succession arrested in movement and in indexed timing arrangement so that the holes 100 in the pallets will accurately register with the then subjacent pins 28 of the lower clamp head. Each pallet bearing its individual oyster will be required to dwell at the operation station A for a sufficient time to permit of the opera tions of clamping and opening. The pegs 101 are so interspersed among the holes 100 that the lower valve of the oyster is supported thereon in a position in which such lower valve may be contacted by the rising pins 28 through the holes 100 by which the bivalve will be lifted from the pallet through the support of the pins 21 to an elevation where the downwardly projecting pins 29 of the upper clamp 21 will engage the upper valve of the oyster and on final upward movement of the lower clamp member 19 the bivalve as to both valves thereof, will be tightly clamped to the upper and lower clamp members with the pins 28 and 29 being forced inwardly to conform to the irregularities of the upper and lower valves and to grasp the valves tightly so that both valves will be immobilized to the respective grasping means 28 and 29 prior to the twist or partial rotation of the upper clamp member 21 to accomplish the opening of the oyster, the breaking of the hinge joint and the twisting of the adductor muscle to an extent to break it away from one of the valves.

The twisting of the upper clamp member 21 will be timed to occur after the clamp members 19 and 21 have moved into final clamping position upon the bivalve.

After the opening of the bivalve the lower clamp member 19 will be automatically lowered to withdraw its pins 28 downwardly out of the holes 100 to permit the conveyor to resume its intermittent movement and convey the opened bivalve to the unload station C, While a fresh bivalve is brought to the operating station A.

Incident to this subsequent downward withdrawing movement of the lower clamp member 19 the opened oyster will be returned to the lower position in which its lower valve will again rest upon the pegs 101 upon which the opened oyster is then eventually carried to the unload station C where the opened oyster is removed by hand or otherwise.

Referring more particularly to FIGURE 16, the sequence of operations is as follows:

(1) The bivalve is shown as resting on the pegs 101 and has arrived at the operation station A in a position below the upper clamp head 21*.

(2) Low pressure air is admitted to the conduit or head space 150, such action being controlled by cam actuated valve synchronized by cam shaft.

(3) Central pin 29 is projected downwardly until its apex engages the oyster at the point D.

(4) Lower clamping head then rises, elevating the pins 23 into contact with the lower valve and lifting the oyster from the pegs 101 toward the upper pins 29 The central pin 29* is still in contact with the upper valve and this central pin will also be deflected upwardly against its lower air pressure. The function of the pin is to retain the axis (cleavage line between shells) of the valve substantially horizontal until the bivalve is firmly clamped between the upper and lower pins 29 and 28 (5) Low pressure in head space 150 is bled to atmosphere via cam valve but the center pin 29 remains in the position as pushed upwardly incident to the rising movement of the bivalve.

(6) Then twist of upper clamping head 21 turns the upper valve to open the bivalve.

While the lower clamp head may carry the bivalve upwardly to the upper head, it is preferred that, by the use of both rocker arms 63 and 70, both heads are made to approach one another and the upper head thereupon has the additional rotary movement which affects the twist and the final opening of the bivalve.

As the lower head is moved downwardly following the twisting operation, its pins 28 will be pulled downwardly through the holes 100 in the pallets 80 of the conveyor, thus affording a stripping operation to remove any foreign matter that may be clinging to the pins.

Referring to FIGURES 16 and 17, when the bivalve is lifted on the lower pins 28 and the upper clamp head 21 lowered with the shaft 66, the upper valve will encounter the stripping plate 103 arresting further descent of this plate and its sleeve 104. Meanwhile further downward movement of the shaft 66 causes head 21 to move down Within and relatively to sleeve 104, permitted by the pipe 1 descending in sleeve slot 10 1 The pins 29 however, continue their downward movement with the shaft 66 and head 21 so that the lower end portions of the pins 29 emerge downwardly through the holes 102 in the stripping plate and under the pressure in the chest 151 take the pattern of the upper valve and tightly grip such upper valve. The bivalve is then subject to opposing pressures of the lower pins 28* and the upper pins 29 and will be clamped tightly therebetween whereby when twist is imparted to the upper shaft 66 and head 21 the upper valve will be turned through a desired angular distance to open the bivalve, break the hinge joint and sever the attachment of the adductor muscle from at least one of the valves.

When the lower pins 28 subsequently descend the upper valve will be withdrawn from the upper pins 29 and from the stripping plate 103, permitting the plate and sleeve to fall at the time when the upper clamp head begins to rise and consequently the parts will be restored to the position of FIGURE 16 after the lower end portions of the pins have been subjected to a strippingv action by reason of the relative movement of the pins and walls of the holes 102 in the stripping plate 103. The stop member 104 will prevent dismemberment of the sleeve and upper clamp head and will also define the normal relation of the lower ends of the pins 29 to the holes 102 in the stripping plate 103.

Twist begins when rotating projection 109 engages anvil 108 (FIGURE 13), causing hub 105 to rotate until 10 roller 116 climbs up inclined section 119 of cam rail 119, at which time the projection 109 moves upwardly out of the path of the anvil 108.

The spring (FIGURE 14), which has been distended during the movement of roller 116 from declining end portion 119 of the cam rail around to the ascending portion 119 comes into play on the disengagement of projection 109 from anvil 108 and causes reverse rotation of shaft 107 and return of the mechanism including the rotary upper clamp head 21 to its initial position.

When roller 116 rotates off high side of cam 119 and declines down the slope 119 the cam roller is then supported on cam plate 117 in the lowermost position permitting projection 109 and anvil 108 to again be in the same plane of engagement, but not necessarily engaged or in contact. The angular position of plate 117 clamped by nut 118 determines minimum angle of twist, namely, where projection 109 and anvil 108 lose their disengagement.

Although we have disclosed herein the best forms of the invention known to us at this time, we reserve the right to all such modifications and changes as may come within the scope of the following claims.

What is claimed is:

1. A machine for opening bivalves comprising (a) means for mechanically supporting and clamping an oyster in an orientation in which the plane of the cleavage between the valves is substantially horizontal and the valves are immobilized to said means, and

(b) means associated with the supporting and clamping means for rotating one of the valves relatively to the other valve in said plane while maintaining their axis of rotation substantially in alignment to open the bivalve.

2. A machine for opening bivalves comprising (a) at least two clamp members,

(b) one at least of the members movable toward and from the companion member to clamp and support a bivalve therebetween and when opened to free the bivalve,

(c) means associated with each member for immobilizing the engaged valve to the member, and

((1) means for rotating at least one member relatively to the associated member together with the entrained valve about an axis within the confines of the outline of the shell of the valve to open the bivalve.

3. A machine for opening bivalves comprising (a) clamp means for receiving the lower valve and supporting the bivalve in an orientation in which the plane of cleavage between the valves is substantially horizontal and having (b) means for grasping the external rough surface of the lower valve to present substantial edgewise relative movement between the lower valve and said clamp means,

(c) a second clamp means movable toward and from the first clamp means for engaging the upper valve and holding the bivalves to the first clamp means and having (d) means for grasping the external rough surface of the upper valve to prevent substantial relative movement between the upper valve and said second clamp means, and

(e) means for twisting at least one of the grasping means and its entrained valve in a substantially horizontal direction relatively to the other valve while maintaining the axis of twist within the confines of the shells outline to open the bivalve.

4. A machine for opening bivalves comprising (a) clamp means for receiving the lower valve and supporting the bivalve in an orientation in which the plane of cleavage between the valves is substantially horizontal and having (b) means for grasping the external rough surface of the lower valve to prevent substantial edgewise relative movement between the lower valve and said clamp means,

(c) a second clamp means movable toward and from the first clamp means for engaging the upper valve and holding the bivalve to the first clamp means and having (d) means for grasping the external rough surface of the upper valve to prevent substantial relative movement between the upper valve and said second clamp means,

(e) means for moving at least one of the grasping means and its entrained valve in a substantially horizontal direction relatively to the other valve to open the bivalve, at least one of the grasping means comprising (f) a plurality of grasping members, and

(g) means for yieldably projecting the grasping members from their clamp means (h) so that on clamping action the irregularities of the shell will cause the grasping members to be retracted proportionately to form a cavity generally conforming to the pattern of the exterior surface of the included valve.

5. A machine for opening bivalves as claimed in claim 4 in which said grasping members are (i) solid round pins.

6. A machine for opening bivalves as claimed in claim 5 in which said pins have (j) valve contacting outer ends which are recessed and having thin marginal edges.

7. A machine for opening bivalves as claimed in claim 4 in which the projecting means comprises (i) fluid pressure supplied chests on the clamp means to which the inner ends of the grasping members are exposed.

8. A machine for opening bivalves comprising (a) clamp means having (b) shell-grasping means movably mounted to the clamp means and yieldably projected toward one another for encountering opposite valves and re tracted thereby to form cavities substantially in the pattern of the external surfaces of the valves on closing of the clamp means,

(c) means for immobilizing the grasping means in said pattern to their respective clamp means, and

(d) means for moving at least one grasping means relatively to the other grasping means parallel to the plane of cleavage between the valves for displacing a valve relatively to companion valve to open the bivalve.

9. A machine for opening bivalves as claimed in claim 8, in which said last-named means ((1) causes said one grasping means to move in an angular movement substantially about the adductor muscle as a center to twist substantially free the attachment of the adductor muscle at least to one of the valves and to break the hinge joint between the valves.

10. A machine for opening bivalves as claimed in claim 8 in which said immobilizing means (c) comprises (e) means binding the shell-grasping means to the clamp means.

11. A machine for opening bivalves as claimed in claim 8 in which said shell-grasping means (b) comprises (e) gangs of pins slidably fitted to the clamp means (a) and (f) fluid-pressure chests movable with the clamp means into which inner ends of the pins (e) are entered exposed to the fluid pressure.

12. A machine for opening bivalves comprising (a) at least two clamp chambers,

(b) deformable shell-grasping means mounted to the members in position to encounter the external uneven surfaces of opposing valves,

(c) means to close the members on a bivalve so that 12 the shell-grasping means is deformed to the pattern of the shell, and

((1) means to shift at least one of the clamp members and its shell-grasping means relatively to the other clamp member to displace the entrained valve for opening the bivalve.

13. A machine for opening bivalves comprising (a) clamp means for clamping a bivalve therebetween and moving one valve relatively to the other to perform an opening operation, and

(b) conveying means moving between the clamping means for carrying bivalves to the clamping means and when opened to carry the bivalves to a removal area and having openings for permitting the clamping means to engage opposite valve of the bivalve.

14. A machine for opening bivalves as claimed in claim 13, further comprising (c) support means on the conveying means on which the bivalves are initially placed and on which such bivalves are transported to the clamp means and to the removal area.

15. A machine for opening bivalves as claimed in claim 13, further comprising (c) pallets in which the openings are made incorporated in the conveying means.

16. A machine for opening bivalves as claimed in claim 13, further comprising (c) actuating means for the conveying means for moving the latter step-wise with dwell periods therebetween at the clamp means.

17. A machine for opening bivalves as claimed in claim 13, in which the clamping means includes (c) at least two clamping members, and

(d) operating means for moving at least one of the clamping members through the openings and the included bivalve against the other clamping member.

18. A machine for opening bivalves as claimed in claim 13, in which said clamp means includes (c) upper and lower clamp members,

(d) means for lifting the lower clamp member at least partially through the openings of the conveying means and also for engaging and lifting the included bivalve into clamping engagement with the upper clamp member, and

(e) twist means for at least partially rotating the upper clamp member during such engagement to turn the upper valve relatively to the lower valve in an opening operation.

19. A machine for opening bivalves as claimed in claim 13, in which the clamp means includes (c) upper and lower clamp members mounted to move toward and from one another for clamping a bivalve therebetween,

(d) said lower clamp member movable at least partially through the openings of the conveying means to lift the incident bivalve on said conveying means upwardly from the conveying means to a position where its upper valve is firmly grasped by the upper clamp member and after the opening operation lowering the opened bivalve onto the conveyor and continuing to lower to withdraw downwardly from the openings of the conveying means, and

(e) twist means for partially rotating the upper clamp member in a sequence immediately following the clamping engagement of the bivalve between the two clamp members for opening the bivalve.

20. A machine for opening bivalves as claimed in claim 19, further comprising (f) valve-grasping pins on said clamp members projecting toward one another,

(g) the openings in said conveying means being (h) a group of holes corresponding in number and pattern to agree with the valve-grasping pins of the lower clamp member to receive such pins upwardly 

1. A MACHINE FOR OPENING BIVALVES COMPRISING (A) MEANS FOR MECHANICALLY SUPPORTING AND CLAMPING AN OYSTER IN AN ORIENTATION IN WHICH STHE PLANE OF THE CLEAVAGE BETWEEN THE VALVES IS SUBSTANTIALLY HORIZONTAL AND THE VALVES ARE IMMOBILIZED TO SAID MEANS, AND (B) MEANS ASSOCIATED WITH THE SUPPORTING AND CLAMPING MEANS FOR ROTATING ONE OF THE VALVES RELATIVELY TO THE OTHER VALVE IN SAID PLANE WHILE MAINTAINING THEIR AXIS OF ROTATION SUBSTANTIALLY IN ALIGNMENT TO OPEN THE BIVALVE.
 31. THE PROCESS OF OPENING BIVALVES WHICH ARE FROZEN TO AND INCLUDING THE INTERNAL MEAT AND INTERNAL JUICES SO AS TO IMMOBILIZE THE MEAT AND JUICES COMPRISING (A) CLAMPING THE FROZEN BIVALVE BETWEEN SHELL-GRASPING MEMBERS, AND (B) PARTIALLY ROTATING AT LEAST ONE OF THE MEMBERS RELATIVELY TO THE OTHER MEMBER IN A PLANE SUBSTANTIALLY PARALLEL TO THE LINE OF CLEAVAGE BETWEEN THE VALVES TO OPEN THE FROZEN BIVALVE AND EXPOSE THE FROZEN MEAT AND JUICES WITHOUT LOSS OF THE LATTER. 